Using the composite equation of the angular displacement vectors of the particle and composite equation of the rotating angular displacement vectors of rigid,this article has defined three-dimensional angular vector and its arithmetic regulation,in the end,the article has set up fundamental theory system of angular vector space.

Based on the engineering geologic section model and rock mass parameter of left bank slope of Longtan Hydropower Station,the influential factors were analyzed with orthogonal analysis of toppling rock slope,the range of dominance of toppling slope,was proposed and the topping condition with displacement vector angle in the same nod of different models were also analyzed.

Through the analysis on deformation property and the basic constitution of different stability evolution stages of the accumulative-formation slope, it is found that the surface displacement vector angles of slope are constituted of whole sliding vector angles compressive displacement vector angle, plastic deformation vector angle and creeping deformation vector angle.

After the characteristics of grey displacement vector angle of Xintan Landslide are analysed,it is found that there are similar dynamic characteristics between grey diSplacement vec-tor angle and the state of la ndslide stability.

Using the grey theory, this paper makes a treatment of the monitoring data of landslide displacement) and finds out the grey displacement vector angle.